Threaded connections between tubular segments or joints of tubular conduit or pipe, such as oilfield tubulars and similar conduits, can be formed by providing a large torque to complimentary male and female threaded members, at the ends thereof, to engage the male and female threaded members in mating relationship. The magnitude of the force used to form the connection can vary depending on the dimensions and/or tolerance of the members. During use, conduits, which are used to contain fluid flow, must be connected using a torque sufficient to fully or substantially engage the threads to form a fluid-tight seal therebetween. Tubular conduits that must withstand significant fluid pressures, such as drill pipe and other oilfield tubular conduit, require a significant torque (up to 50,000 foot-pounds, or more) to form a fluid-tight seal. Even when properly torqued, multiple, redundant seals are often required to ensure fluid-tight integrity under anticipated fluid pressures without permitting damage to the members.
Application of significant torque to tubular members can cause galling, stripping, and/or cross-threading of the threads. Galling and similar destructive deformation can create difficulty when attempting to engage or disengage a threaded connection, and can prevent reuse of the deformed tubular members. Typically, to reduce and/or prevent galling, tubular threads must be treated, such as through application of a coating of tin, zinc, or other metals and/or alloys, or by “sugar blasting” the threads with fine grains of sand. When a threaded connection is placed under a significant lateral force, bending force or combination of such forces, such as when used within a directional borehole, one or more of the threads can become disengaged, compromising the integrity of the connection and seal.
A need exists for a threaded connection between threaded tubulars that can be torqued without galling or otherwise damaging the threads to enable a stronger connection and the reuse or re-engagement of the threaded tubulars.
Another need exists for a fluid connection assembly comprising a first fluid connector having a male end and second fluid connector having a female end, wherein the male and female ends, each, comprise parallel threads for threadable engagement to form a flush threaded connection, which provides greater efficiency in the handling and controlling of tensile strength.
A further need exists for a threaded connection between a first fluid connector having a male end with parallel threads and a second fluid connector having a female end with parallel threads, with both ends comprising symmetrical shoulders and corresponding faces, which can be joined and maintained in contact to form a metal-to-metal seal as the connection experiences tension or is bent during downwell operations.